Suresha Bheemappa | Visvesvaraya Technological University (original) (raw)

Papers by Suresha Bheemappa

Warasan Loha, Watsadu lae Lae, Jun 13, 2024

Composites and Nanocomposites, 2013

ABSTRACT The objective of this research article is to evaluate the mechanical properties of glass... more ABSTRACT The objective of this research article is to evaluate the mechanical properties of glass fabric reinforced epoxy (G-E), graphite filled G-E (Gr-G-E), alumina filled G-E (Al2O3 -G-E), silicon dioxide filled G-E (SiO2-G-E) and silicon carbide filled G-E (SiC-G-E) composites. The amount of fillers used is 0, 5 and 7.5 % in G-E composite. All composites were fabricated using hand lay-up technique followed by compression moulding.The mechanical properties such as tensile, flexural and impact strengths were investigated in accordance with ASTM standards. From the present experimental investigation, it was found that the presence of micro-fillers improved the hardness of G-E composite. Further, the study revealed that the flexural strength of SiC / SiO2 filled G-E was higher than that of unfilled G-E and other micro-filler filled G-E composites.

Biomass Conversion and Biorefinery, Dec 13, 2022

Journal of Manufacturing Processes

Reinforcement of glass fibers at the weld joint interface of polyamide 66 (PA66) was investigated... more Reinforcement of glass fibers at the weld joint interface of polyamide 66 (PA66) was investigated aiming to improve the weld strength but rather found to improve the tribological properties. The weld strength of glass fiber reinforced polyamide 66 was found to be in the range of 46 %-52 % of that of the parent material. The dry sliding wear behavior of the friction stir welded polyamide 66 with and without glass fiber strengthening was investigated in this experimental study, using a pin-on-disk wear tester. The worn surface topography and morphology were analyzed via white light interferometry and scanning electron microscope, respectively. The wear study confirmed that PA66 reinforced with high fiber content of 20 % by weight of polymer (GF/PA66) yielded a minimum specific wear rate and coefficient of friction.

Electric Power Components and Systems, 2020

This research investigation was performed to seek the bio-based alternative for the liquid insula... more This research investigation was performed to seek the bio-based alternative for the liquid insulator in transformers. The current investigation aims to examine the effect of oil rancidity on the dielectric strength of bio-based oils along with the other preliminary examinations like fire point, flash point, and viscosity. Sunflower oil portrayed the notable performance under all the tests that were conducted. The exposure to the conditioned atmosphere uncovered the presence of a huge variation in DBV of bio-based oil the affirming that the rancidity of oil degrades the insulating ability of the oil. The multi-objective optimization tool MOORA (Multi-Objective Optimization based on Ratio Analysis) was utilized to optimize and select the best oil sample. Upon considering the outcome of all the tests performed and MOORA, sunflower oil was ranked first.

The objective of this study is to evaluate the performance of HSS and Carbide drills by measuring... more The objective of this study is to evaluate the performance of HSS and Carbide drills by measuring the various drilling parameters such as thrust, torque, delamination, specific cutting pressure and surface roughness. Two micro-fillers, viz. Alumina and Graphite were used. The amount of fillers addition was 5 wt% in G-E composite. All composites were fabricated using hand lay-up technique followed by compression moulding. Drilling experiments were conducted with HSS and carbide drills under various cutting conditions, keeping diameter of the drill constant. Topography of drilled hole surfaces were analyzed through SEM micrographs. From the experimental investigation, it was found that plain/neat composites produced better quality holes compared to particulate filled composites when machined with HSS drills. Carbide drills produced better quality holes in particulate filled composites, especially with graphite filled ones.

International journal of innovative research and development, 2014

The aim of this investigation is to study the three-body abrasive wear behavior of different weig... more The aim of this investigation is to study the three-body abrasive wear behavior of different weight percentage (wt%) filled organo-modified montmorillonite (oMMT) with constant wt% of treated and untreated coir sheath (CS) in unsaturated polyester (USP) resin. There-body abrasive wear of the hybrid composites were studied under different filler loading, treatment of the coir sheath, and abrading distance. The results of the abrasive wear test revealed that the wear volume increases with increase in abrading distance and specific wear rate is high for the untreated composites (UTCs) compared to alkali treated composites (ATCs) and silane treated composites ( STCs) . STCs with 1 wt% oMMT-filled USP hybrid composite exhibited better abrasive wear resistance compared to UTCs and ATCs. Different wear mechanisms were observed on the worn surfaces of the composites, including pitting, micro- and/or macro- cracks, as well as crack propagation of the matrix in the transverse direction.

Instrumentation Science & Technology

The influence of silane treated aluminum oxide (Al2O3) and molybdenum disulphide (MoS2) microfill... more The influence of silane treated aluminum oxide (Al2O3) and molybdenum disulphide (MoS2) microfillers on three-body abrasive wear behaviour of carbon fabric reinforced epoxy (C‐E) composites was evaluated using a rubber wheel abrasion tester. Three-body wear tests were conducted at different loads/abrading distances. The experimental results showed that the wear volume increased with increasing abrading distance/load while the specific wear rate decreased with increasing abrading distance. It was found that silane treated aluminum oxide (Al2O3) and molybdenum disulphide (MoS2) as fillers enhanced the abrasion resistance of the C‐E composites. Further, the specific wear rate depends on applied load, the type of filler and filler loading. The factorial design was carried out to investigate the effects of individual operating parameters like normal load, abrading distance, type of filler and filler loading and the combined effect of these same parameters, and their interactions with the...

Glass-fiber reinforced polymer composites (GFRP) are finding number of applications in space, avi... more Glass-fiber reinforced polymer composites (GFRP) are finding number of applications in space, aviation, ship and automotive industry. Although GFRP’s are generally fabricated to near-set-shape, there often is a need to conduct some additional machining operations. Drilling of composite materials is a very common and an additional machining operation used in industry to carryout the assembly of composite components. However, drilling of composite materials present a number of problems such as force fluctuation, rapid tool wear and delamination.In the present study, effect of Alumina micro-filler addition on thrust force and delamination and subsequent surface damage occurring has been presented. During the investigation, the glass fiber reinforced polymer composites with and without micro-filler has been drilled with HSS drill under different cutting conditions. The thrust force and torque are monitored on line with a drill tool dynamometer under varying conditions of speed and feed....

Materials & Design, 2012

ABSTRACT The present investigation aims to develop carbon fabric reinforced epoxy composite (C–E)... more ABSTRACT The present investigation aims to develop carbon fabric reinforced epoxy composite (C–E) with addition of different weight fraction of silicon carbide filler as secondary reinforcement and to characterize mechanical and tribological properties. The experiments were designed according to Taguchi’s (L9) orthogonal array to optimize experimental runs. In order to assess the wear behavior of composites satisfying multiple performance measure, grey-based Taguchi approach has been adopted. Two-body abrasive wear tests were carried out using pin-on-disc apparatus with four process parameters, filler content, grit size, load and abrading distance. Analysis of variance was applied to determine the significant parameters that affect abrasive wear. The results indicated that, addition SiC particles into C–E composite increased the wear resistance considerably. Highest wear resistance of C–E composite was achieved by incorporation of 10 wt.% of SiC. Observation showed that filler content and abrasive grit size have the most significant influence on abrasive behavior of C–E composite. After the thorough analysis of factors optimal factor setting have been suggested.

Wear, 2009

In this experimental study, the dry sliding wear and two-body abrasive wear behaviour of graphite... more In this experimental study, the dry sliding wear and two-body abrasive wear behaviour of graphite filled carbon fabric reinforced epoxy composites were investigated. Carbon fabric reinforced epoxy composite was used as a reference material. Sliding wear experiments were conducted using a pin-on-disc wear tester under dry contact condition. Mass loss was determined as a function of sliding velocity for loads of 25, 50, 75, and 100 N at a constant sliding distance of 6000 m. Two-body abrasive wear experiments were performed under multi-pass condition using silicon carbide (SiC) of 150 and 320 grit abrasive papers. The effects of abrading distance and different loads have been studied. Abrasive wear volume and specific wear rate as a function of applied normal load and abrading distance were also determined. The results show that in dry sliding wear situations, for increased load and sliding velocity, higher wear loss was recorded. The excellent wear characteristics were obtained with carbon-epoxy containing graphite as filler. Especially, 10 wt.% of graphite in carbon-epoxy gave a low wear rate. A graphite surface film formed on the counterface was confirmed to be effective in improving the wear characteristics of graphite filled carbon-epoxy composites. In case of two-body abrasive wear, the wear volume increases with increasing load/abrading distance. Experimental results showed the type of counterface (hardened steel disc and SiC paper) material greatly influences the wear behaviour of the composites. Wear mechanisms of the composites were investigated using scanning electron microscopy. Wear of carbon-epoxy composite was found to be mainly due to a microcracking and fiber fracture mechanisms. It was found that the microcracking mechanism had been caused by progressive surface damage. Further, it was also noticed that carbon-epoxy composite wear is reduced to a greater extent by addition of the graphite filler, in which wear was dominated by microplowing/microcutting mechanisms instead of microcracking.

Applied Mechanics and Materials, 2014

In this work, enhancement of viscoelastic behaviour and thermal stability of hybrid friction comp... more In this work, enhancement of viscoelastic behaviour and thermal stability of hybrid friction composites has been synergistically investigated. Five different friction composites were fabricated by varying weight % of basalt fiber against BaSO4 content. Dynamic mechanical analysis (DMA) was carried out to assess the temperature dependent viscoelastic behaviour of composites. Basalt fibre addition improves dynamic modulus such as storage modulus (E'), loss modulus (E") and lowers the damping factor (tan δ) values. Thermal degradation behaviour and presence of volatile elements in the composites was studied using thermo gravimetric analysis (TGA). Higher amount of BaSO4 resulted in higher thermal stability and lower % of weight loss. Fourier transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD) analysis were employed to characterize the composites.

Materials & Design, 2013

The carbon fabric reinforced epoxy (C-E) with different loading of organo-modified montmorillonit... more The carbon fabric reinforced epoxy (C-E) with different loading of organo-modified montmorillonite (oMMT) hybrid composites were prepared using hand lay-up technique followed by autoclave curing. The effects of oMMT loading on mechanical properties and three-body abrasive wear behaviour of hybrid composites have been investigated. The three-body abrasive wear tests with different loads/abrading distances were performed at room temperature using a Rubber wheel abrasion test apparatus. Experimental results obtained from tensile tests indicate that the tensile strength and modulus of hybrid composites increases with the increment of oMMT nanoparticles. Furthermore, the C-E specimens with 5 wt% oMMT loading exhibit superior tensile strength than those that do not contain any oMMT nanoparticles. The abrasive wear test results showed that the wear volume increased with increasing abrading distance and the specific wear rate decreased with increasing abrading distance/load for all hybrid composites. Among the oMMT loaded hybrid composite samples tested, 5 wt% oMMT loaded hybrid composite showed a promising trend. Free volume property of the hybrid composites measured from positron lifetime spectroscopy seems to correlate well with the mechanical and wear properties. Finally, the different wear mechanisms were observed on the worn surface of the hybrid composites including micro and macro cracks, pitting, as well as debonding and breakage of the fibers by scanning electron microscopy, atomic force microscopy coupled with vision measure scope.

Journal of Minerals and Materials Characterization and Engineering, 2013

Drilling is indispensable process and it cannot be avoided for joining composite structures used ... more Drilling is indispensable process and it cannot be avoided for joining composite structures used in various engineering applications. In this research article, the influence of drilling parameters on thrust force and torque of silica (SiO 2) and alumina (Al 2 O 3) filled into glass fabric reinforced epoxy (G-E) composites are analyzed. Drilling experiments are conducted on these composite materials using BATLIBOI make radial drilling machine. Two different drill bits (HSS and cemented carbide) are used for the experimentation. The influence of drilling parameters like cutting speed and feed on thrust force and torque on drilling of particulate filled G-E composites has been carried out. The experimental results indicated that the thrust force and torque were increased with increasing feed and cutting speed for all the composites tested. Further, it is observed that the carbide drill performed better than HSS drill during drilling of particulate filled G-E composites. The drilled surfaces are examined using scanning electron microscopy (SEM) and damage mechanisms are discussed.

Materials Science and Engineering: A, 2007

Three-body abrasive wear behaviour of carbon-epoxy (C-E) and glass-epoxy (G-E) composites has bee... more Three-body abrasive wear behaviour of carbon-epoxy (C-E) and glass-epoxy (G-E) composites has been investigated. The effect of abrading distance, viz., 270, 540, 810 and 1080 m and different loads of 22 and 32 N at 200 rpm have been studied. The wear volume loss and specific wear rate as a function of load and abrading distance were determined. The wear volume loss increases with increasing load/abrading distance. However, the specific wear rate decreases with increase in abrading distance and increases with the load. However, C-E composite showed better abrasion wear resistance compared to G-E composite. The worn surface features have been examined using scanning electron microscope (SEM). SEM micrographs of abraded composite specimens revealed the high percentage of broken glass fiber compared to carbon fiber and also better interfacial adhesion between epoxy and carbon fiber.

Journal of Thermal Analysis and Calorimetry, 2012

ABSTRACT Nanocomposites, based on tetrabromo-bisphenol-A epoxy and aniline formaldehyde condensat... more ABSTRACT Nanocomposites, based on tetrabromo-bisphenol-A epoxy and aniline formaldehyde condensates, containing 5 and 10 % organically modified montmorillonite (O-MMT), were prepared. The morphologies of these nanocomposites were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The influences of O-MMT on the dynamic cure kinetics, thermal stability, and mechanical properties were investigated by differential scanning calorimetry, thermogravimetric analysis, and non-destructive ultrasonic testing techniques. The XRD and SEM results indicated a good dispersion of O-MMT within the epoxy matrix. The relation between the activation energy, E (a), and the degree of cure, alpha, for the examined systems was obtained by applying model-free isoconversional Kissinger-Akahira-Sunose method. As alpha increases, E (a) increases gradually, almost independent of the amount of O-MMT. The dynamic cure kinetics of the neat epoxy system as well as its nanocomposites were described by estA k-Berggren, [SB (m, n)], autocatalytic model. The O-MMT enhances the thermal stability of the examined epoxy system. The results of the mechanical properties indicated that the addition of O-MMT enhances the Young's and shear elastic modulus and microhardness. The values of these parameters increase with increasing O-MMT loading.

Journal of Reinforced Plastics and Composites, 2012

The changes that can occur in particulate filled and carbon fabric reinforced epoxy polymer matri... more The changes that can occur in particulate filled and carbon fabric reinforced epoxy polymer matrix (carbon–epoxy) composites with aging (temperature change) can affect its application, performance, and life time. Fiber and particulate-reinforced composites are known to posses the high strength and attractive wear resistance in dry siding conditions. Though reinforcement and/filler type are known to control the properties, less is known about their abrasive wear performance especially with SiC particulates. How these composites performed in abrasive wear situation needs a proper understanding. Hence in this investigation, reports on dynamic mechanical and three-body abrasive wear behavior of carbon–epoxy and silane-treated SiC particulates filled carbon-epoxy composites. The dynamic mechanical analysis test were conducted using DMA Q800 instrument and abrasive wear tests were conducted using the Rubber wheel abrasive wear tester. From the dynamic mechanical analysis result, it was fo...